Abstract
Energy transfer (ET) is an important route to manage the population density of excited states, giving rise to spectrally tunable emission that is valuable for multicolor imaging and biological tracking. In this paper, a case study of GdF3 nanoparticles (NPs) codoped with Yb3+ and Er3+ was used to experimentally and theoretically investigate the ET mechanisms under near-infrared and violet excitation. Red-to-green ratio (RGR) is used as a primary evaluating protocol, and the power-dependent luminescence and Er3+ 4I13/2 luminescence behavior are used to identify the corresponding conjectures about ET mechanisms. Compared with the four common upconversion (UC) models, a joint effect of energy-back-transfer, multiphonon relaxation, and linear decay depletion mechanisms for the Er3+ 4I13/2 manifold was proposed for the UC process based on UC spectra for samples with different dopant concentrations. Meanwhile, the varying RGR could also be observed from downshifting (DS) emission spectra. The ET mechanism for t...
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
